Two-dimensional metal-organic frameworks (MOFs) refer to a class of porous materials composed of metal ions coordinated to organic ligands. MOFs can be designed with peculiar physical, chemical, and structural properties by taking advantage of their tunability. These properties can be applied in a wide range of fields, including energy storage, photocatalysis, heterogeneous catalysis, sensing and proton conductors, and optical and electronic devices. In this thesis, I focus on several metal-organic structures that are constructed on both metal and Van der Waals substrates.

This thesis consists of three projects as below:

In the first project, I synthesize and characterize two new 2D-cMOFs, namely Ni₃(BHO_−6H) and Co-BHO. In Ni₃(BHO_−6H), Ni atoms comprise a Kagome lattice and the screened...[ Read more ]

Two-dimensional metal-organic frameworks (MOFs) refer to a class of porous materials composed of metal ions coordinated to organic ligands. MOFs can be designed with peculiar physical, chemical, and structural properties by taking advantage of their tunability. These properties can be applied in a wide range of fields, including energy storage, photocatalysis, heterogeneous catalysis, sensing and proton conductors, and optical and electronic devices. In this thesis, I focus on several metal-organic structures that are constructed on both metal and Van der Waals substrates.

This thesis consists of three projects as below:

In the first project, I synthesize and characterize two new 2D-cMOFs, namely Ni₃(BHO_−6H) and Co-BHO. In Ni₃(BHO_−6H), Ni atoms comprise a Kagome lattice and the screened Kondo effect may be observed. The Co-BHO system exhibits long-range lattice periodicity but displays disordered electronic states and magnetic features.

In the second project, I design and synthesize a series of 2D-MOFs M₃(HAT)₂ (M= Fe, Co, Ni, Cu), on the Au (111) and Ag (111) surface. The symmetric double-step like features observed in the vicinity of the Fermi level in M₃(HAT)₂ (M= Fe, Co, Ni) are believed to originate from spin excitations resulting from spin-spin coupling.

In the third project, I synthesize and characterize Ni₃(HAT)₂ and Co₃(HAT)₂ MOFs on both Au (111) and HOPG substrates. These MOFs are effectively decoupled from HOPG substrate. The STS data confirm that these MOFs are intrinsic narrow bandgap 2D MOFs, which have great potential to be used as highly conductive 2D materials.

In summary, I synthesized two series of 2D MOFs on metal and HOPG substrates and characterized their structural, electronic, and magnetic properties. These studies open new opportunities to investigate intrinsic electronic and magnetic properties in 2D MOFs.